Delayed presentation of melanoma-associated retinopathy and subsequent resolution with cytoreduction surgery

Abstract

To present a case of melanoma-associated retinopathy (MAR) which manifested 26months prior to a formal diagnosis of melanoma. Case report. A 72-year-old female presented with bilateral continuous photopsia consistent with MAR of 7-months duration. At this point, visual function appeared normal with the exception of mildly impaired colour vision (10/17 Ishihara plates). The flash electroretinographic (ERG) revealed extinguished rod responses, a normal a-wave and reduced b-wave (electronegative ERG) on the maximal combined response, absent oscillatory potentials and broadened a-wave trough on the cone response. Multifocal ERG (mfERG) responses were delayed and demonstrated atypical morphology. Nineteen months after the initial presentation, her visual symptoms had progressed significantly with constant debilitating photopsia in combination with 13kg weight loss. Biopsy of a now evident left axillary mass demonstrated a metastatic high-grade malignant melanoma. No primary was detected, and an axillary lymph node clearance was undertaken. Subsequently, visual symptoms resolved with corresponding improvement in the ERG over the next 18months. Rod responses recovered such that the amplitude was at the lower limit of normal and the mfERG response delay lessened. Unfortunately, the melanoma recurred and the patient passed away 6months later. Visual symptoms did not recur. We present a case which demonstrates MAR may precede the formal diagnosis of melanoma by up to 26months. The potential for improvement in the rod visual function persists over a period of years with normalisation of an electronegative waveform. In this case, cytoreductive surgery resulted in complete resolution of the MAR, which did not return even with a recurrence of the tumour.